The spectrum of thermally stimulated currents in rock samples from KTB drilling: preliminary results

The technique of thermally stimulated depolarization currents (TSDC) was applied to fine grained amphibolite rock samples extracted from KTB drilling. Each sample was cooled down to liquid nitrogen temperature and consequently heated at a constant rate b = 4 K/min while at the same time it was shorted by a sensitive electrometer. Thermocurrent glow curves were detected in the range from 180 to 360 K. By applying the TSDC method, an effort was made to carry out a preliminary analysis of the TSDC spectrum.

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Technology of thermally stimulated diagnostics of anisotropy and optical axes in crystals

Modern Electronic Materials ◽

10.3897/j.moem.6.4.65351 ◽

2020 ◽

Vol 6 (4) ◽

pp. 125-132

Author(s):

Viktor M. Timokhin ◽

Vladimir M. Garmash ◽

Valentin A. Tedzhetov

Keyword(s):

Relaxation Time ◽

Melting Point ◽

Electric Field ◽

Liquid Nitrogen ◽

Optical Axis ◽

Liquid Nitrogen Temperature ◽

Breakdown Field ◽

Optical Axes ◽

Polarization Temperature ◽

Thermally Stimulated Depolarization

For implementing the technology of thermally stimulated diagnostics of anisotropy and optical axes in crystals, the sample is thermostated at a temperature not exceeding the melting point, an electric field not exceeding the breakdown field is applied to the sample and polarization is produced for a time greater than the relaxation time at this temperature. After that, without switching off the electric field, the sample is cooled to the liquid nitrogen temperature, following which the field is switched off, the sample is linearly heated to a temperature above the polarization temperature and the resultant thermally stimulated depolarization (TSD) spectra taken along and perpendicular to the optical axis of the crystal are examined. When comparing the spectra the presence of anisotropy is detected and the direction of the optical axes is determined from the magnitude and presence of the TSD maxima.

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Preparation of Cu–Y–Ba alloys by mechanical alloying

Journal of Materials Research ◽

10.1557/jmr.1990.1802 ◽

1990 ◽

Vol 5 (9) ◽

pp. 1802-1805 ◽

Cited By ~ 10

Author(s):

E. Batalla ◽

E. G. Zwartz

Keyword(s):

Mechanical Alloying ◽

Ball Milling ◽

Liquid Nitrogen ◽

High Energy ◽

High Energy Ball Milling ◽

Crystalline Phases ◽

X Ray ◽

Preliminary Results ◽

Fine Grained ◽

Energy Ball

Preliminary results of producing Cu–Y–Ba metallic precursors to high Tc superconductors by high energy ball milling are reported. Mechanical alloying of Cu, Y, and Ba powders (various stoichiometries) produced either amorphous, mixed crystalline/amorphous, or fine grained crystalline powders, as shown by their x-ray spectra. None of the powders exhibited flux exclusion down to a temperature of 1.4 K. The YBa2Cu3 precursor consisted of a mixture of crystalline phases. After being pressed into a pellet and sintered, it was found to be superconducting at liquid nitrogen temperatures.

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Electron Probe Microanalysis of Frozen Hydrated Kidneys, Isolated Cells, and Cultured Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054595 ◽

1982 ◽

Vol 40 ◽

pp. 402-403 ◽

Cited By ~ 1

Author(s):

Claude Lechene

Keyword(s):

Liquid Nitrogen ◽

Electron Probe Microanalysis ◽

Electron Probe ◽

Cultured Cells ◽

Liquid Nitrogen Temperature ◽

Elemental Content ◽

Isolated Cells ◽

Renal Tubular Cells ◽

Diamond Saw ◽

Saw Blade

Electron probe microanalysis of frozen hydrated kidneysThe goal of the method is to measure on the same preparation the chemical elemental content of the renal luminal tubular fluid and of the surrounding renal tubular cells. The following method has been developed. Rat kidneys are quenched in solid nitrogen. They are trimmed under liquid nitrogen and mounted in a copper holder using a conductive medium. Under liquid nitrogen, a flat surface is exposed by sawing with a diamond saw blade at constant speed and constant pressure using a custom-built cryosaw. Transfer into the electron probe column (Cameca, MBX) is made using a simple transfer device maintaining the sample under liquid nitrogen in an interlock chamber mounted on the electron probe column. After the liquid nitrogen is evaporated by creating a vacuum, the sample is pushed into the special stage of the instrument. The sample is maintained at close to liquid nitrogen temperature by circulation of liquid nitrogen in the special stage.

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Field-Ion Microscopy of BCC Metals: A Study of Image Differences and Topographical Variations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071016 ◽

1973 ◽

Vol 31 ◽

pp. 114-115

Author(s):

O. T. Inal ◽

L. E. Murr

Keyword(s):

Liquid Nitrogen ◽

Liquid Nitrogen Temperature ◽

Surface Atom ◽

Image Brightness ◽

Field Ion Microscopy ◽

Topographic Features ◽

Bcc Metals ◽

Electron Orbital ◽

Ion Microscopy ◽

Field Ion Microscope

When sharp metal filaments of W, Fe, Nb or Ta are observed in the field-ion microscope (FIM), their appearance is differentiated primarily by variations in regional brightness. This regional brightness, particularly prominent at liquid nitrogen temperature has been attributed in the main to chemical specificity which manifests itself in a paricular array of surface-atom electron-orbital configurations.Recently, anomalous image brightness and streaks in both fcc and bee materials observed in the FIM have been shown to be the result of surface asperities and related topographic features which arise by the unsystematic etching of the emission-tip end forms.

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The Effects of Drying Techniques on Clay-Rich Soil Texture

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052341 ◽

1974 ◽

Vol 32 ◽

pp. 466-467

Author(s):

T. G. Naymik

Keyword(s):

Critical Point ◽

Liquid Nitrogen ◽

Liquid Nitrogen Temperature ◽

Drying Methods ◽

Air Drying ◽

Freeze Dried ◽

Critical Point Drying ◽

Set Up ◽

The Relationship ◽

Quartz Grains

Three techniques were incorporated for drying clay-rich specimens: air-drying, freeze-drying and critical point drying. In air-drying, the specimens were set out for several days to dry or were placed in an oven (80°F) for several hours. The freeze-dried specimens were frozen by immersion in liquid nitrogen or in isopentane at near liquid nitrogen temperature and then were immediately placed in the freeze-dry vacuum chamber. The critical point specimens were molded in agar immediately after sampling. When the agar had set up the dehydration series, water-alcohol-amyl acetate-CO2 was carried out. The objectives were to compare the fabric plasmas (clays and precipitates), fabricskeletons (quartz grains) and the relationship between them for each drying technique. The three drying methods are not only applicable to the study of treated soils, but can be incorporated into all SEM clay soil studies.

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Water accumulation as a function of temperature on specimens in an electron microscope cold stage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142219 ◽

1986 ◽

Vol 44 ◽

pp. 114-115 ◽

Cited By ~ 2

Author(s):

M.K. Lamvik ◽

D.A. Kopf ◽

S.D. Davilla ◽

J.D. Robertson

Keyword(s):

Electron Microscope ◽

Mass Loss ◽

Liquid Helium ◽

Liquid Nitrogen ◽

Liquid Nitrogen Temperature ◽

Liquid Helium Temperature ◽

Helium Temperature ◽

Cold Stage ◽

Water Accumulation ◽

Better Than

Last year we reported1 that there is a striking reduction in the rate of mass loss when a specimen is observed at liquid helium temperature. It is important to determine whether liquid helium temperature is significantly better than liquid nitrogen temperature. This requires a good understanding of mass loss effects in cold stages around 100K.

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